Gas turbine engine performance is very dependent on maintaining a tight seal between a high pressure region and a low pressure region. These regions are present throughout the gas turbine engine including regions between the turbine stages, compressor stages, and other locations.
To add to the complexity of sealing the high pressure region from the low pressure region, many of the seals in the gas turbine engine are established between moving parts. In one particular application, a shaft seal prevents a hot, high pressure gas from moving between a housing and a rotating shaft into a low pressure gas. Current sealing arrangements such as C-seals, E-seals, bellows seals, and Garlock seals tend to wear quickly. The wear of these seals is further exacerbated by leakage through these seals.
Some manufacturers use a plurality of non-metallic seals in a piston ring fashion. These seals may work well in a low temperature environment. However, the non-metallic seals tend to have reduced mechanical strength at higher temperatures. The reduced mechanical strength allows the seals to lose their shape or fail to return to their original shape. Leaking increases as the seals loose their mechanical strength. At higher temperatures, the leakage rates will oxidize the seal and further increase leakage. In some instances leakage may create problems controlling the gas turbine engine.
The present invention is directed to overcome one or more of the problems as set forth above.